Just what does the human mind do when it thinks? Here we must conjecture a little.

Thinking seems to occur on several levels. (The term “level” will be used to distinguish one kind of mental activity from another.[1] These thinking activities overlap, and are not actually separate and distinct. They could be described as different "modes of thought,” but separating the process into three “levels” aids explanation.)

Before we begin, let us distinguish what happens autonomically—the brain’s control of body functions mentioned in section one. As has been stated, what the brain does reflexively is not really considered to be thinking. For example when confronting danger, the body prepares for flight or fight - the pulse races, the lungs ventilate, the digestion is suspended, the stomach and bowels may be emptied (hence such expressions as sick with worry and frightened shitless).

These emotional responses are fast and dirty survival mechanisms. Except insofar as they affect mood and thus rational thinking we will mostly ignore this kind of uncontrollable activity.

↑It may help some to use the word “consciousness” instead of the word “thinking” when reading this section. I have chosen to use “thinking” because I wish to emphasize differences (“levels” of thinking) that are harder to separate when using the word “consciousness.” (Consciousness is further, although briefly, discussed in a postscript to this chapter, Consciousness And Conscience.)